Dell Dimension C521 Processor Compatibility

Hi NCageAllDay,

Welcome to the Community.

Dell Dimension C521 is compatible with AMD Athlon 64 X2 Dual-Core, AMD Athlon 64 and AMD Sempron processors. I would suggest you to update the BIOS before processor upgrade. Please click the link mentioned below which will take you to the drivers website:

http://dell.to/QjjZDA

Enter the Service Tag of the computer and choose the Operating System installed on the computer. Please update the latest version of BIOS available.

Thanks & Regards
Manshu S
#iworkfordell

Also- I was looking to upgrade my RAM as well, what would be some better alternatives to the standard 1GB it comes with?

Also- I was looking to upgrade my RAM as well, what would be some better alternatives to the standard 1GB it comes with?

Hi NCageAllDay,

Thank you for the reply.

Dell Dimension C521 is compatible with maximum 4 GB memory. Please click the link mentioned below for available options:

http://dell.to/12cK7ci

Thanks & Regards
Manshu S
#iworkfordell

Will I need an upgraded PSU with the processor selection you listed shesagordie?

NCageAllDay

No.

Bev.

I am late, however if you want maximum power you can upgrade to Athlon 64 x2 6000+ - it was tested to be working on multiple E521, C521 is the slim version, motherboard is the same.

This is the list of possible 6000+ processors

Option 1. 125 watt. AMD Athlon 64 X2 6000+ - ADX6000IAA6CZ (ADX6000CZBOX). eBay link. This one is not for you, it runs too hot.

Option 2. 89 watt. AMD Athlon 64 X2 6000+ - ADV6000IAA5DO (ADV6000DOBOX). eBay link. This one has 3.1 GHz, but only 1 MB cache.

Option 3. 89 watt. AMD Athlon 64 X2 6000+ - ADA6000IAA6CZ (ADA6000CZBOX). eBay link. This one a bit slower than Option 2 at 3.0 GHz, very little          difference, but has 2 MB cache, which is much better - clear winner from 3 options.

I cannot advice on eBay buying strategy, have no clue here, I guess you want free shipping and ability to return.

A few years ago it was a good discussion on this matter, 2 important things from this thread, first RAM can be upgraded beyond Dell recommendations to 8 GB (if you have, or you planning to install 64 bit OS) and second, if you are willing to place 6000+ CPU you would have to downgrade your BIOS since latest BIOS for your system has limitation against CPU upgrades. If the links below not working this is driver download page for C521, could be useful anyway.

This is the list of all BIOS versions for your C521, I cannot state which one exactly will recognize 6000+, but most likely not the latest one v1.1.10.

Also, a few more thoughts. Your power supply is 280 watt, no upgrades here, since it is proprietary, so if you want graphic card upgrade the best choice would be Sapphire 7750 low profile card which will work with your power supply (you have PCIE x16 one slot). If you are looking for manuals, you found them already<ADMIN NOTE: Broken link has been removed from this post by Dell>.

I hope I am not that late.

I have 4gigs, one 2GB module, one 1GB module and two 512mb modules. 

I have 4gigs, one 2GB module, one 1GB module and two 512mb modules.

I know this is an old thread, but I was hoping somebody might lend a hand.  My C521 has bios 1.1.4 on it.  I would like to upgrade the CPU and I was wondering if it would work without updating the bios.  The reason I ask is because I have Windows 7 Ultimate on it, and when I try to run the 1.1.11 bios, It keeps saying unsupported system in the bios flash menu, and the start button is grayed out.  I've heard it wasn't compatible with windows 7, but I really have no clue.  Anyone out there that can help?

xXEblisXx  The Athlon 64 X2 6000+ 3.0Ghz 89W Windsor, will work.  Prior to installing the processor, check that you have the latest BIOS version 1.1.11 installed, with BIOS version 1.1.4 support for AMD was added. The default fan and PSU should be fine. Bev.

I am late, however if you want maximum power you can upgrade to Athlon 64 x2 6000+ - it was tested to be working on multiple E521, C521 is the slim version, motherboard is the same.

Hi guys. I notice you have both contributed to multiple threads/forums regarding this subject so I'm hoping you can help

After researching, I came to the conclusion that the AMD Athlon 64 X2 6000+ 3000 MHz 89 Watt (Windsor) was one of, if not the best you could buy for the Dell Dimension C521.

My original CPU is the AMD Athlon 64 X2 3800+ 2000 MHz 89 Watt (Windsor) and here is a link to compare them:

Compare CPU's

My motherboard is 0HY175 and at my first attempt the BIOS was 1.0.3

After inserting the new CPU and as the computer gradually started up, it was obvious there was a problem due to the fan running super fast/loud. I had read that disabling Cool'n'Quiet might help but unfortunately it didn't. so the next step was to upgrade the BIOS to 1.1.4 which is what I am currently running. I was hopeful this would solve the problem due to the added AMD support but I'm afraid the problem persists. Between each step I put the old CPU back in as I was scared the new CPU could do more harm than good. I have scoured the web for more suggestions but I can't find any hence my reason for posting.

I'm not sure further upgrading the BIOS to 1.1.10 or 1.1.11 will help so I'll wait for a reply.

Another thing I might add is that I didn't apply thermal paste in case I encountered a problem like this and from the speed/noise of the fan, I doubt thermal paste is the solution but I will wait for a reply.

The only other info I can think of adding right now is the CPU-Z report for my original CPU and a shot of the BIOS screen which seems to recognise both CPU's when installed:

Any help will be greatly appreciated! I look forward to any replies. Cheers

sohohoho

Did you check to see if the power button LED, solid green, blinking green, solid amber, blinking amber, while the AMD Athlon 64 X2 6000 was installed ?

Together with the sequence of the four Diagnostic Lights on the front panel, see page 49 here?

http://ftp.dell.com/Manuals/all-products/esuprt_desktop/esuprt_dimension_desktops/dimension-c521_service%20manual_en-us.pdf    

I cannot see any reason why the AMD Athlon 64 X2 6000+ 3000 MHz 89w [Windsor], should not work with the BIOS version 1.1.4, unless the processor itself has issues.

Personally, I would clean the base of the heatsink and the top of the processor, apply thermal compound to see if this makes a difference.

No difference, then replace the processor.

A manual giving the procedures for cleaning and reapplying the thermal compound, can be found HERE.

You need a small tube of thermal compound, this can be purchased from any computer store.

Where did you download the BIOS version 1.1.4 from, as I noticed Dell only lists version 1.1.11 on their download site?

http://www.dell.com/support/home/us/en/04/Drivers/DriversDetails?driverId=R164018&fileId=2731117833&osCode=WW1&productCode=dimension-e521&languageCode=EN&categoryId=BI

Bev.

Hey Bev, many thanks for your reply.

First, I would like to point out that member kisianik had posted links to the previous BIOS versions above:

...if you are willing to place 6000+ CPU you would have to downgrade your BIOS since latest BIOS for your system has limitation against CPU upgrades. If the links below not working this is driver download page for C521, could be useful anyway. 1.1.10 6/26/2007 3:23:22 PM 1.1.4 1/1/2007 7:55:02 AM 1.1.2 12/6/2006 10:43:30 AM 1.0.3 10/6/2006 4:57:16 PM 1.0.0 9/15/2006 2:23:56 PM This is the list of all BIOS versions for your C521, I cannot state which one exactly will recognize 6000+, but most likely not the latest one v1.1.10.

Off topic but I notice one of the benefits of 1.1.10 is to "Improve Flash stability under Windows". I have Flash disabled because it makes Firefox unstable. Do you think this BIOS version would help? and would this BIOS version accept the the 6000+ CPU?

Back on topic, I am completely stunned to find that after applying thermal compound (Arctic MX-4) the CPU now seems to be running smoothly!? Cool'n'Quiet is disabled, I am yet to test the CPU with Cool'n'Quiet enabled. Have you ever experienced thermal compound to be such a fundamental element? I never would have imagined, especially considering the problem was noticeable within 60 second of starting up. Also, the 3800+ was working fine after I had already cleaned off the thermal compound.

If we haven't got the thermal compound to thank, then the only other variable is that the computer has been off for +8 hours. Could this have helped after upgrading the BIOS?

Just to be sure about the health of the CPU, is there any way that I can run diagnostics on it, a program maybe? I am still sceptical because so far I haven't noticed much speed difference between the 3800+ and the 6000+ when starting up the system and loading/running programmes etc.

Here is some data:

Kind regards,

Ross.